1. Field of the Invention
The present invention relates to a system for removing contaminated surface soil. More particularly, the present invention relates to a system for mapping the location of contaminated surface soil prior to removal operations, monitoring the location of the removal apparatus to reduce the amount of uncontaminated soil removed and updating the mapping after the removal of contaminated soil.
2. Description of the Related Art
There are many sites where the surface soil is contaminated by hazardous materials such as chemicals, heavy metals, NORM (Naturally Occurring Radioactive Material) or other radioactive materials. Typical examples include radioactive mineral mining and processing sites, oil drilling and production sites, and oil field maintenance areas where NORM contaminated pipe and other equipment was cleaned. Normally the contaminated material lies at or near the surface and is often mixed with the surface or top layers of soil.
Environmental clean up of these areas requires that the contaminated soil be collected and stored or processed to remove or otherwise retain the contaminated materials. A common technique to accomplish this task is to remove the surface soil on the site with standard earth moving equipment. During such removal process, it is necessary to provide for the entrapment of any contaminants that would otherwise become airborne, primarily by windblown action. Thus, it is desirable to control dust during the removal process.
Additionally, since objects in waste soil tend to migrate toward the surface, it is preferable to remove the surface soil in thin layers so that the buried objects and other contaminants can be detected before they are disturbed. This removal process frequently results in excessive clean or uncontaminated soil being removed along with the contaminated soil, increasing the cost of removing, transporting, and processing or storing the removed soil. Handling, processing, and storage costs increase in direct proportion to the amount of material to be processed. Minimizing the amount of soil to be processed therefore minimizes the cost. Further, removing the clean soil increases the time spent performing the removal process, further increasing costs.